code: def calc_pck3d(dists, threshold=0.5):
      n, c = dists.shape
      return (dists < threshold).sum() / (n * c)
  
imports: import os
  import torch
  import torch.optim
  import numpy
  from sklearn.metrics import auc
label_desc: Use image node_id 23 for calling a global function with example usage: calc_pck3d(dists, threshold) and returns: unknown